材料期刊网

用金相法扫描电镜、X射线衍射等手段对发生爆炸的高压消防气体钢瓶进行了宏观、微观形貌、材质、腐蚀产物及其原因进行了分析.结果表明：在瓶壁内侧尤其是靠近下部的位置发现有较多腐蚀凹坑；裂纹始于内壁，向外壁发展，且断口靠近内壁表面首先开裂的区域覆盖较多腐蚀产物；腐蚀产物主要是FeCO3；内壁有较多有利于腐蚀发生的条带组织，并且在内壁上发现许多始于腐蚀凹坑的穿晶裂纹，具有应力腐蚀开裂特征；其爆炸原因主要是，由于瓶壁靠近底部的位置发生了较严重的二氧化碳水溶液下的应力腐蚀所致.

The failure of highpressure bottle for extinguisher was investigated by means of visual examination,chemical analysis,SEM observation，Xray analysis and metallographic examination.Pitting was observed on internal surface of the exploded bottle,especially in the area near the bottom.SEM observation showed that cracks initiated from internal surface of the bottle and developed outwords to the outer surface.Corrosion product covered on the cracked area near the internal surface of the bottle was proved mainly to be FeCO3 by XRay analysis.Metallographic examination revealed that the internal surface showed a striplike microstructure,which was favor to corrosion and many transcrystalline cracks initiated from pits on the internal surface with clear character of stress corrosion cracking.All analysis results showed that stress corrosion cracking(SCC)caused by carbon dioxide solution on the internal surface near the bottom was the main reason of explosion.